1. Field of the Invention
The present invention relates to an automotive air conditioner, more particularly, to an arrangement for the automotive air conditioner unit having heat exchangers which is disposed in approximately horizontal direction and introduces the air generated by a blower from lower sides of the heat exchangers.
2. Description of the Related Art
Generally, a conventional automotive air conditioner adopts so called xe2x80x9clateral layoutxe2x80x9d. This lateral layout is, as shown in FIG. 17, that a fan unit 1, a cooler unit 2a and a heater unit 2b are arranged in line in the lateral (width) direction of the vehicle.
FIG. 18 shows the manner in which the lateral layout air conditioner is mounted within the vehicle. The vehicle has an instrumental panel or dashboard P. The fan unit 1, the cooler unit 2a and the heater unit 2b collectively occupy a almost half space (which is formed in front of a passenger seat) in the dashboard P along the width direction of the vehicle.
Recently, a vehicle is provided with a great number of electronic components such as computers, a compact disk player, a passenger air bag and other automotive accessories. This results in a decrease in the space within the dashboard P and thus, makes it difficult to mount such a lateral layout air conditioner within the dashboard.
As shown in FIG. 19, there is shown another type of conventional air conditioner 2 arranged centrally within a vehicle and including, as a unit, a cooler or evaporator 21 and a heater core 22. The evaporator 21 and the heater core 22 are arranged one after the other in the longitudinal direction of the vehicle. A fan unit 1 is offset laterally from the central portion of the vehicle.
This type of arrangement is so called center layout. The center layout provides a sufficient space within the dashboard to mount the evaporator 21 and the heater core 22 since these components are both located at the center of the vehicle. However, since these heat exchangers (evaporator 21 and heater core 22) are vertically arranged one above the other in a longitudinal direction of the vehicle, it is necessary to provide an air duct in front of the evaporator 21 so as to receive an air from the fan unit 1. By the same way, it is necessary to provide another air duct behind the heater core 22 to allow an air flow from the heater core 22.
Consequently, those air ducts results in an increase in the overall length of the air conditioner.
This increase makes it difficult to mount a blow mode selector behind the heater core 22. To this end, the blow mode selector may be arranged above the heater core 22. However, this arrangement brings about an increase in the height of the air conditioner.
Thus, such a center layout air conditioner is also difficult to mount with a lot of electric components in the dashboard.
In view of the foregoing, it is an object of the present invention to provide a compact automotive air conditioner which enables mounting heat exchangers within a narrow vehicular space.
It is another object of the present invention to provide an automotive air conditioner which promotes drainage of condensation from an evaporator.
To achieve the above objects, the present invention adopted the following construction.
In one preferred mode of the present invention, an automotive air conditioner includes a blower, a cooling heat exchanger, a heating heat exchanger, and a blow mode selector.
The blower blows an air. The cooling heat exchanger is approximately horizontally disposed between a dashboard within a passenger compartment and an engine room and receives the air from its bottom side to an upward direction. The heating heat exchanger is approximately horizontally disposed over the cooling heat exchanger and heats the air. The blow mode selector is disposed downstream of the heating heat exchanger and changes the direction of the air flown after the air is heated to a controlled temperature by the heating heat exchanger.
In another preferred mode of the present invention, the blower is disposed between a dashboard within a passenger compartment and an engine room and offset in width direction of a vehicle from the center of a width of vehicle.
Preferably, the cooling heat exchanger gradually inclines downward along the direction of the air flow which is generated by the blower.
Preferably, the cooling heat exchanger is inclined at an angle of 10 to 30 degrees with respect to a horizontal plane.
Preferably, the air conditioner includes a case for directing the air from the blower to the cooling heat exchanger. The case has a condensed water drain pipe for draining condensed water at a position below an air flow end of downwardly inclined the cooling heat exchanger.
Preferably, the automotive air conditioner includes guide elements located below the cooling heat exchanger. The guide elements are substantially in contact therewith.
Preferably, the case has a concave and convex surface having step shape and extending in a width direction of the case to equal an air blow speed distribution measured by an air blow speed of the air introduced into the cooling heat exchanger at a bottom surface of the cooling heat exchanger.
Preferably, the blower includes a scroll casing disposed approximately horizontally, and the scroll casing has a winding end portion connected to an air passage below the cooling heat exchanger. Further, an air guide plate is disposed on a downstream side of the cooling heat exchanger and extends from the scroll casing along the air flow direction. In this way, the blow air by the blower from the scroll casing is guided by the air guide plate, and the air blow speed distribution in the longitudinal direction of the automobile can be uniformed. Accordingly, the uniform heat exchange can be performed in each portion of the cooling heat exchanger, thus improving the heat exchanging efficiency and contributing to the uniformity of the air blow speed distribution of the air flowing into the heating heat exchanger.
Preferably, an upper surface of the air guide plate contacts with a bottom surface of the cooling heat exchanger so that the air guide plate supports the said cooling heat exchanger.
Preferably, the air guide plate partitions an air passage below the cooling heat exchanger into plural independent passages.
Preferably, the air guide plate includes a curved portion on an end thereof on a side of a centrifugal fan of the blower, and the curved portion is bent smoothly along the air flow from the centrifugal fan.
Preferably, a unit case for containing the cooling heat exchanger is included, and the winding end portion is connected to a portion corresponding to a lower side portion of the cooling heat exchanger, of the unit case. Further, a portion leading from the winding end portion to the unit case, of the scroll casing, extends approximately parallel to a width direction of the automobile, and the air guide plate is disposed approximately parallel to a width direction of the automobile.
Preferably, a plurality of air distributing plates is disposed in a space between the cooling heat exchanger and the heating heat exchanger, for uniforming air blow speed distribution of air in the heating heat exchanger in a width direction of the automobile.
Preferably, a unit case for containing the cooling heat exchanger is included, and the unit case includes a stepped concave and convex portion on a portion thereof corresponding to a lower portion of the cooling heat exchanger, for uniforming air blow speed distribution of air flowing into the cooling heat exchanger in a width direction of the automobile.
Preferably, an air conditioning unit case for containing the cooling heat exchanger and the heating heat exchanger and for forming an air passage in which air generated by said blower passes is included, and a direction of the air passage is changed from a horizontal direction to a vertical direction toward the downstream side. Further, the cooling heat exchanger includes a plurality of tubes in which heating medium for being heat exchanged with air which is generated by said blower passes, and a corrugated fin connected between each pair of the adjacent tubes, and the corrugated fin has a fin flat surface and is provided with louvers for guiding air which is generated by said blower toward an inclination direction against the fin flat surface. The inclination direction being is so as to offset non-uniformity of air blow speed distribution of air due to the changing direction of the air passage in said air conditioning unit case.
Preferably, the inclination directions of the louvers of the corrugated fin on an upstream side and on the downstream side of said fin flat surface are reversed against each other, and the inclination direction of the louver of the corrugated fin at least on the downstream side is set so as to offset the non-uniformity of air blow speed distribution of air.
Preferably, the cooling heat exchanger inclines downward with a minute angle along the forwarding direction of the air flow which is generated by said blower, and the plurality of tubes is disposed so as to extend below said cooling heat exchanger along the blowing direction of the air flow which is generated by said blower. Further, the cooling heat exchanger includes a tank portion for distributing and receiving the heating medium against the plurality of tubes on an upper end portion thereof in the inclination direction, and the inclination direction of the louver of the corrugated fin at least on the downstream side is set so as to direct the air flow by the blower toward the tank portion.
In another preferred mode of the present invention, blower is disposed so as to be offset from a central portion of a dashboard in a width direction of an automobile, a cooling heat exchanger is approximately horizontally disposed within a dashboard, for receiving from its bottom side the air blown by the blower, cooling the air, and leading the cooled air toward an upward direction, and a heating heat exchanger is approximately horizontally disposed over the cooling heat exchanger in the central portion of a dashboard and for heating the air.
In further another preferred mode of the present invention, a blower is disposed so as to be offset from a central portion of a dashboard in a width direction of an automobile, a cooling heat exchanger is approximately horizontally disposed within a dashboard, for receiving from its bottom side the air blown by the blower, cooling the air, and leading the cooled air toward an upward direction, and a blow mode selector is disposed over the cooling heat exchanger and for changing the blowing direction of the air passing through the cooling heat exchanger.
In still another preferred mode of the present invention, a blower is disposed so as to be offset from a central portion of a dashboard in a width direction of an automobile, a heating heat exchanger is approximately horizontally disposed, for receiving the air from its bottom side the air blown by the blower, heating the air, and leading the heated air toward an upward direction, and a blow mode selector disposed over the heating heat exchanger and for changing the blowing direction of the air passing through the heating heat exchanger.
According to these preferred modes, both of the cooling heat exchanger and the heating heat exchanger are located substantially horizontally and laminated vertically (one above the other), a vertical space for the heat exchanger portion can be greatly reduced. As a result, the vertical dimension of the air conditioning unit can be made sufficiently smaller than that of the conventional center-layout unit.
Further, because the vertical dimension of the air conditioning unit can be made sufficiently small as described above, even when the blow mode selector is disposed over the heating heat exchanger, the vertical dimension of the entire air conditioning apparatus can be suppressed from increasing.
Further, because it is unnecessary to provide blowing ducts on the front and rear sides of the heat exchanger portion, the dimension in the longitudinal direction of the vehicle can also be reduced.